• Varsha Hanumant Bhong
• Dr. Sangeeta Sinha

Fishes are very specific and sensitive to their environmental conditions. Major factors that affect the development, survival and growth of the fishes are the pH, salinity, hardness, dissolved oxygen (DO) and temperature. The present study is concerned on the effect of increase in the artificial sea water concentration and bleaching powder on the survival rate of freshwater carp Catla catla. The artificial sea water and bleaching powder is used for the present study. The freshwater fish, Catla catla fingerlings were exposed to sub- lethal concentration of artificial sea water and bleaching powder for 24, 48, 72 and 96 hours and percent mortality rate was calculated. At the end of each exposure period, fishes were sacrificed and tissues such as gills and liver were removed and analysed for lipid damage, histopathological damage and significant changes were recorded in various anti-oxidative enzymes. The percent mortality and specific activity of lipid peroxidation increased with the increasing concentration of sea water with bleaching powder. The activity of CAT and SOD (antioxidant enzymes) increased and GPx and GR activity decreased as compared to control. The extent of damage to the gills and liver tissues was proportionate with increased concentration of artificial sea water and bleaching powder. The value of percent sea water with bleaching powder that Catla can tolerate which is drawn through this experiment can be used as one of the standard analysing parameters for establishing the fish farm.

bleaching powder, artificial sea water, Catla catla, sub-lethal toxicity, antioxidant enzymes, histopathology.

"To Study the Combined Sub- lethal Effect of Bleaching Powder and Artificial Sea Water on Catla catla", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.7, Issue 10, page no.1866-1882, October-2020, Available :http://www.jetir.org/papers/JETIR2010244.pdf

"To Study the Combined Sub- lethal Effect of Bleaching Powder and Artificial Sea Water on Catla catla", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.7, Issue 10, page no. pp1866-1882, October-2020, Available at : http://www.jetir.org/papers/JETIR2010244.pdf